So lets put this into perspective. If they ban them, and they go on the black market. Wouldnt that mean criminals who would buy them on the black market would have them and people who buy guns to hunt and protect themselves would be without arms?

You can use a knife to cut fruit, or stab people. You can use a hammer to hammer a nail in the wall or kill people. The point is people who want to cause harm to others, whether it be through building bombs or using other means will find a way.

Why do people who would never do such a thing lose the right to bear arms because of someone elses crime or behavior?

The issue is the different mentalities of different people. Because most of us here would never have that thought enter our mind to do what these fucking wastes of flesh did to these children this morning.